Unacceptable with Opportunity to Supplement Alt. to ASME Code Requirements for Repair of Reactor Vessel Head Penetrations (TACs ME6071, ME6072, ME6073, and ME6074)ML111330653 |
Person / Time |
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Site: |
Byron, Braidwood ![Constellation icon.png](/w/images/b/be/Constellation_icon.png) |
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Issue date: |
06/06/2011 |
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From: |
Nicholas Difrancesco Plant Licensing Branch III |
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To: |
Pacilio M Exelon Nuclear, Exelon Generation Co |
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DiFrancesco N, NRR/DORL/LPL3-2, 415-1115 |
References |
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TAC ME6071, TAC ME6072, TAC ME6073, TAC ME6074 |
Download: ML111330653 (5) |
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Category:Code Relief or Alternative
MONTHYEARML22307A2462022-11-10010 November 2022 Proposed Alternative to the Requirements of the American Society of Mechanical Engineers Boiler & Pressure Vessel Code (EPIDs L-2021-LLR-0035 and L-2021-LLR-0036) RS-22-110, Supplemental Information - Proposed Alternatives Related to the Steam Generators and Request.2022-09-20020 September 2022 Supplemental Information - Proposed Alternatives Related to the Steam Generators and Request. RS-22-036, Supplemental Information - Proposed Alternative for Examination of Pressurizer Circumferential and Longitudinal Shell-to-Head Welds and Nozzle-to-Vessel Welds2022-03-10010 March 2022 Supplemental Information - Proposed Alternative for Examination of Pressurizer Circumferential and Longitudinal Shell-to-Head Welds and Nozzle-to-Vessel Welds ML21280A0782021-10-27027 October 2021 Proposed Alternative to Use of the American Society of Mechanical Engineers Boiler and Pressure Vessel Code Case N-893 (Epids L-2020-LLR-0147 and L-2020-LLR-0148) ML21230A2062021-09-0303 September 2021 Proposed Alternative to Use ASME OM Code Case OMN-28 ML21216A2202021-08-0505 August 2021 Proposed Alternative to Eliminate Certain Documentation Requirements for Pressure Retaining Bolting ML21134A0062021-08-0303 August 2021 Proposed Alternatives to the Requirements of the American Society of Mechanical Engineers Boiler & Pressure Vessel Code (Epids L-2020-LLR-0099 and L-2020-LLR-0100) RS-21-008, Request for Alternative: One-Time Deferral of Follow-Up Inspection for Reactor Pressure Vessel Head Penetration Nozzles with Mitigated Alloy 600/82/182 Peened Surfaces in Accordance with 10 CFR 50.55a(z)(2)2021-01-25025 January 2021 Request for Alternative: One-Time Deferral of Follow-Up Inspection for Reactor Pressure Vessel Head Penetration Nozzles with Mitigated Alloy 600/82/182 Peened Surfaces in Accordance with 10 CFR 50.55a(z)(2) ML20269A2002020-09-30030 September 2020 Request to Use a Provision of Later Edition of the ASME Boiler and Pressure Vessel Code, Section XI (EPID L2020-LLR-0117 ML20245E5062020-09-0909 September 2020 Relief from the Requirements of the ASME Code (COVID-19) ML20188A2642020-07-0606 July 2020 Clinton Power Station, R.E. Ginna Station, Limerick Station, Nine Mile Point Station & Peach Bottom Station - Proposed Alternative to Utilize Code Case OMN-26 - Response to Request for Additional Information ML20113F0412020-04-30030 April 2020 Proposed Alternative to the Submittal Schedule for Certain Reports (COVID-19) ML20099D9552020-04-17017 April 2020 Request to Use Provisions in the 2013 Edition of the ASME Boiler and Pressure Vessel Code for Performing Non-Destructive Examinations RS-20-020, Relief Request for Alternative Frequency to Supplemental Indication Requirements of 10 CFR 50.55a(b)(3)(xi)2020-02-28028 February 2020 Relief Request for Alternative Frequency to Supplemental Indication Requirements of 10 CFR 50.55a(b)(3)(xi) ML19269C5342019-09-27027 September 2019 Proposed Alternative to Use Encoded Phased Array Ultrasonic Examination Techniques ML19136A3862019-06-0505 June 2019 Relief from the Requirements of the American Society of Mechanical Engineers Code ML19141A0202019-06-0505 June 2019 Relief from the Requirements of the American Society of Mechanical Engineers Code ML19155A0602019-06-0505 June 2019 Relief from the Requirements of the American Society of Mechanical Engineers Code ML19161A2572019-06-0404 June 2019 BWR Fleet Msv/Srv - Testing Frequency Relief Request NRC Pre-Application Meeting June 4, 2019 ML19035A2942019-02-25025 February 2019 Relief from the Requirements of the ASME Code JAFP-19-0023, Relief Request Associated with the Use of Encoded Phased Array Ultrasonic Examination Techniques in Lieu of Radiography for Ferritic and Austenitic Piping Welds2019-02-15015 February 2019 Relief Request Associated with the Use of Encoded Phased Array Ultrasonic Examination Techniques in Lieu of Radiography for Ferritic and Austenitic Piping Welds RS-19-015, Relief Request 14-RS-1 to Implement Code Case OMN-132019-01-31031 January 2019 Relief Request 14-RS-1 to Implement Code Case OMN-13 ML18318A3342019-01-17017 January 2019 Relief from the Requirements of the American Society of Mechanical Engineers Code ML18331A0372019-01-17017 January 2019 Relief from the Requirements of the American Society of Mechanical Engineers Code ML18347B4192019-01-17017 January 2019 Relief Request I4R-03, Relief from ASME Requirements for the Fourth 10-Year Inservice Inspection Interval Related to Degraded Canopy Seal Welds Associated with Control Rod Drive Mechanism ML18305A3602018-12-0606 December 2018 Relief from the Requirements of the American Society of Mechanical Engineers Code RS-18-125, Proposed Alternative Requirements for the Repair and Examination of Reactor Pressure Vessel Head Penetration Nozzles for the Fourth Lnservice Inspection Interval in Accordance with 10 CFR 50.55a(z)(1)2018-10-11011 October 2018 Proposed Alternative Requirements for the Repair and Examination of Reactor Pressure Vessel Head Penetration Nozzles for the Fourth Lnservice Inspection Interval in Accordance with 10 CFR 50.55a(z)(1) RS-18-123, Request for Alternative Follow-up Inspection for Reactor Pressure Vessel Head Penetration Nozzles with Mitigated Alloy 600/82/182 Peened Surfaces in Accordance with 10 CFR 50.55a(z)(2)2018-09-24024 September 2018 Request for Alternative Follow-up Inspection for Reactor Pressure Vessel Head Penetration Nozzles with Mitigated Alloy 600/82/182 Peened Surfaces in Accordance with 10 CFR 50.55a(z)(2) JAFP-18-0052, Proposed Alternative to Utilize Code Case N-8792018-05-30030 May 2018 Proposed Alternative to Utilize Code Case N-879 JAFP-18-0053, Proposed Alternative to Utilize Code Cases N-878 and N-8802018-05-30030 May 2018 Proposed Alternative to Utilize Code Cases N-878 and N-880 ML17325B5712018-01-10010 January 2018 Non-Proprietary, Request for Relief for Extension of Examination Interval for Reactor Pressure Vessel Head Penetration Nozzles with Mitigated Alloy 600/82/182 Peened Services (CAC No. MF9854; EPID L-2017-LLR-0042) RS-17-168, Request for Relief for Extension of Examination Interval for Reactor Pressure Vessel Head Penetration Nozzles with Mitigated Alloy 600/82/182 Peened Surfaces in Accordance with 10 CFR 50.55a(z)(1)2017-12-20020 December 2017 Request for Relief for Extension of Examination Interval for Reactor Pressure Vessel Head Penetration Nozzles with Mitigated Alloy 600/82/182 Peened Surfaces in Accordance with 10 CFR 50.55a(z)(1) RS-17-168, Braidwood Station, Unit 2, Request for Relief for Extension of Examination Interval for Reactor Pressure Vessel Head Penetration Nozzles with Mitigated Alloy 600/82/182 Peened Surfaces in Accordance with 10 CFR 50.55a(z)(1)2017-12-20020 December 2017 Braidwood Station, Unit 2, Request for Relief for Extension of Examination Interval for Reactor Pressure Vessel Head Penetration Nozzles with Mitigated Alloy 600/82/182 Peened Surfaces in Accordance with 10 CFR 50.55a(z)(1) ML17249A2982017-11-13013 November 2017 Relief from the Requirements of the ASME Code (CAC No. MF9597; EPID L-2017-LLR-0021) ML17249A2412017-09-19019 September 2017 Relief from the Requirements of the ASME Code RS-17-083, Inservice Inspection Program Third Interval Relief Requests 13R-12 and 13R-152017-06-29029 June 2017 Inservice Inspection Program Third Interval Relief Requests 13R-12 and 13R-15 ML17170A0132017-06-26026 June 2017 Proposed Alternative to Eliminate Examination of Threads in Reactor Pressure Vessel Flange (CAC Nos. MF8712-MF8729 and MF9548) ML17095A2682017-03-31031 March 2017 Submittal of Request for Relief for Extension of Examination Interval for Reactor Pressure Vessel Head Penetration Nozzles with Mitigated Alloy 600/82/182 Peened Surfaces: Attachment 1, Relief Request ML17054C2552017-03-15015 March 2017 Request for Relief from Requirements of the American Society of Mechanical Engineers Boiler and Pressure Vessel Code (ASME Code) ML17062A4282017-03-0606 March 2017 Request for Relief from the Requirements of the ASME Code ML17047A0382017-02-24024 February 2017 Request I4R-11 Relief from the Requirements of the American Society of Mechanical Engineers Boiler and Pressure Vessel Code (ASME Code) ML16327A3182016-12-20020 December 2016 Request I4R-06, Relief from the Requirements of the ASME Code ML16327A3962016-12-20020 December 2016 Request I4R-01, Relief from the Requirements of the ASME Code ML16327A4212016-12-19019 December 2016 Requested Relief from the Requirements of the Asme Code (CAC Nos. MF7641 and MF7642) ML16306A3662016-11-0808 November 2016 Request I4R-08, Relief from the Requirements of the ASME Code ML16230A2372016-09-0606 September 2016 Fleet Request for Proposed Alternative to Use ASME Code Case N-513-4 (CAC Nos. MF7301-MF7322) ML16162A2112016-06-29029 June 2016 Request for Use of Alternative ML16109A3372016-04-27027 April 2016 Relief from the Requirements of the ASME Code (CAC Nos. MF6715, MF6716, MF6717, and MF6718) ML15173A4362015-06-30030 June 2015 Relief from the Requirements of the ASME Code RS-15-170, Submittal of Relief Requests Associated with the Fourth Inservice Testing Interval2015-06-22022 June 2015 Submittal of Relief Requests Associated with the Fourth Inservice Testing Interval 2022-09-20
[Table view] Category:Letter
MONTHYEARIR 05000456/20230042024-02-0202 February 2024 Integrated Inspection Report 05000456/2023004 and 05000457/2023004 IR 05000454/20230042024-02-0202 February 2024 Integrated Inspection Report 05000454/2023004 and 05000455/2023004 ML24025C7242024-01-29029 January 2024 Notification of NRC Baseline Inspection and Request for Information; Inspection Report 05000456/2024002; 05000457/2024002 IR 05000457/20230112024-01-25025 January 2024 2B Auxiliary Feedwater Pump Diesel Fuel Oil Dilution Report 05000457/2023011 and Preliminary Greater than Green Finding and Apparent Violation ML24022A2722024-01-23023 January 2024 Request for Information for an NRC Post-Approval Site Inspection for License Renewal Inspection Report 05000454/2024011 ML24018A0362024-01-17017 January 2024 Paragon Energy Solutions, Defect with Detroit Diesel/Mtu Fuel Injectors P/N R5229660 Cat Id 0001390618 RS-24-004, Proposed Alternative to the Distribution Requirements of ASME Code Table IWC-2411-1 for the Steam Generators2024-01-11011 January 2024 Proposed Alternative to the Distribution Requirements of ASME Code Table IWC-2411-1 for the Steam Generators ML23348A2162023-12-15015 December 2023 Exemption from Select Requirements of 10 CFR Part 73 (EPID L-2023-LLE-0030 (Security Notifications, Reports, and Recordkeeping and Suspicious Activity Reporting)) IR 05000456/20200232023-12-15015 December 2023 Baseline Security Inspection Document; 05000456/2023/402; 05000457/2023/402 ML23320A1762023-12-13013 December 2023 Exemption from Select Requirements of 10 CFR Part 73 (EPID L-2023-LLE-0027 (Security Notifications, Reports, and Recordkeeping and Suspicious Activity Reporting)) ML23277A0032023-12-11011 December 2023 Issuance of Amendments Regarding Adoption of TSTF-370 ML23339A0452023-12-0505 December 2023 Request for Information for an NRC Post-Approval Site Inspection for License Renewal Inspection Report 05000546/2024010 ML23313A1552023-12-0101 December 2023 Review of the Fall 2022 Steam Generator Tube Inspection Report ML23318A5102023-12-0101 December 2023 Relief from the Requirements of the ASME Code IR 05000454/20233012023-11-27027 November 2023 NRC Initial License Examination Report 05000454/2023301 and 05000455/2023301 ML23331A8922023-11-22022 November 2023 Supplement - Braidwood Security Rule Exemption Request ISFSI Docket No. Reference 05000457/LER-2023-001, Submittal of LER 2023-001-00 for Braidwood Station, Unit 2, Train B Auxiliary Feedwater Pump Was Inoperable Due to Degraded Oil in the Crank Case2023-11-17017 November 2023 Submittal of LER 2023-001-00 for Braidwood Station, Unit 2, Train B Auxiliary Feedwater Pump Was Inoperable Due to Degraded Oil in the Crank Case ML23321A0442023-11-17017 November 2023 Notification of Deviation from Electric Power Research Institute (EPRI) Topical Report MRP-227, Revision 1-A, Materials Reliability Program: Pressurized Water Reactor Internals Inspection and Evaluation Guideline BYRON 2023-0065, Unit 2 - Notification of Deviation from Electric Power Research Institute (EPRI) Topical Report MRP-227, Revision 1-A, Materials Reliability Program: Pressurized Water Reactor Internals Inspection and Evaluation Guideline2023-11-17017 November 2023 Unit 2 - Notification of Deviation from Electric Power Research Institute (EPRI) Topical Report MRP-227, Revision 1-A, Materials Reliability Program: Pressurized Water Reactor Internals Inspection and Evaluation Guideline BYRON 2023-0063, Day Inservice Inspection Report for Interval 4, Period 3, (B2R24)2023-11-16016 November 2023 Day Inservice Inspection Report for Interval 4, Period 3, (B2R24) IR 05000454/20230032023-11-13013 November 2023 Integrated Inspection Report 05000454/2023003 and 05000455/2023003 and Exercise of Enforcement Discretion RS-23-117, Supplemental Information Letter for Part 73 Exemption Request - Responses to Request for Confirmatory Information2023-11-10010 November 2023 Supplemental Information Letter for Part 73 Exemption Request - Responses to Request for Confirmatory Information ML23317A1192023-11-10010 November 2023 Constellation Energy Generation, LLC - 2023 Annual Report - Guarantees of Payment of Deferred Premiums RS-23-118, Supplemental Information Letter for Part 73 Exemption Request - Responses to Request for Confirmatory Information2023-11-10010 November 2023 Supplemental Information Letter for Part 73 Exemption Request - Responses to Request for Confirmatory Information ML23313A0852023-11-0909 November 2023 Submittal of 2023-301 Byron Initial License Examination Post-Examination Comments RS-23-114, Proposed Alternative for Examination of Pressurizer Circumferential and Longitudinal Shell-to-Head Welds and Nozzle-to-Vessel Welds2023-11-0101 November 2023 Proposed Alternative for Examination of Pressurizer Circumferential and Longitudinal Shell-to-Head Welds and Nozzle-to-Vessel Welds ML23297A2352023-10-26026 October 2023 Information Request for the Cyber Security Baseline Inspection, Notification to Perform Inspection IR 05000456/20234012023-10-18018 October 2023 Security Baseline Inspection Report 05000456/2023401 and 05000457/2023401 IR 05000456/20230102023-10-18018 October 2023 Functional Engineering Inspection Commercial Grade Dedication Report 05000456/2023010 and 05000457/2023010 RS-23-100, Request for Exemption from Enhanced Weapons, Firearms Background Checks, and Security Event Notifications Implementation2023-10-13013 October 2023 Request for Exemption from Enhanced Weapons, Firearms Background Checks, and Security Event Notifications Implementation RS-23-097, Constellation Energy Generation, LLC, Advisement of Leadership Changes and Submittal of Updated Standard Practice Procedures Plans2023-10-12012 October 2023 Constellation Energy Generation, LLC, Advisement of Leadership Changes and Submittal of Updated Standard Practice Procedures Plans RS-23-108, Proposed Alternative for Examinations of Examination Categories B-B, B-D, and C-A Steam Generator Pressure Retaining Welds and Full Penetration Welded Nozzles2023-10-11011 October 2023 Proposed Alternative for Examinations of Examination Categories B-B, B-D, and C-A Steam Generator Pressure Retaining Welds and Full Penetration Welded Nozzles RS-23-105, Proposed Alternative for Examinations of Examination Category C-B Steam Generator Nozzle-to-Shell Welds and Nozzle Inside Radius Sections2023-10-10010 October 2023 Proposed Alternative for Examinations of Examination Category C-B Steam Generator Nozzle-to-Shell Welds and Nozzle Inside Radius Sections ML23278A0272023-10-0505 October 2023 Operator Licensing Examination Approval - Byron Station, October 2023 RS-23-094, Relief Request I4R-24, Alternative for Post-Peening Reexamination Frequency for Reactor Pressure Vessel Head Penetration Nozzle Number 752023-09-29029 September 2023 Relief Request I4R-24, Alternative for Post-Peening Reexamination Frequency for Reactor Pressure Vessel Head Penetration Nozzle Number 75 RS-23-093, License Amendment to Braidwood Station, Units 1 and 2, and Byron Station, Units 1 and 2, Technical Specifications 3.7.15, Spent Fuel Pool Boron Concentration, 3.7.16, Spent Fuel.2023-09-29029 September 2023 License Amendment to Braidwood Station, Units 1 and 2, and Byron Station, Units 1 and 2, Technical Specifications 3.7.15, Spent Fuel Pool Boron Concentration, 3.7.16, Spent Fuel. ML23251A1622023-09-29029 September 2023 Steam Generator Tube Inspection Reports to Reflect TSTF-577 Reporting Requirements RS-23-091, Relief Request I4R-25, Alternative Requirements for Reactor Pressure Vessel Inservice Inspection Intervals2023-09-26026 September 2023 Relief Request I4R-25, Alternative Requirements for Reactor Pressure Vessel Inservice Inspection Intervals ML23226A0062023-09-19019 September 2023 Review of License Renewal Commitment Number 10 Submittal ML23180A1692023-09-11011 September 2023 Calvert Cliff Units 1 & 2, and R.E. Ginna Plant - Withdrawal of Proposed Alternatives to American Society of Mechanical Engineers (ASME) Requirements (Epids L-2022-LRR-0074, 0076, 0079, 0091, 0092, 0093 and 0094) ML23242A3282023-09-0101 September 2023 Amendment No. 233 Correction IR 05000454/20235012023-08-31031 August 2023 Emergency Preparedness Biennial Exercise Inspection Report 05000454/2023501 and 05000455/2023501 IR 05000454/20230052023-08-30030 August 2023 Updated Inspection Plan for Byron Station (Report 05000454/2023005 and 05000455/2023005) IR 05000456/20230052023-08-30030 August 2023 Updated Inspection Plan for Braidwood Station Report 05000456/2023005 and 05000457/2023005 ML23234A2462023-08-25025 August 2023 Confirmation of Initial License Examination IR 05000456/20230022023-08-0303 August 2023 Integrated Inspection Report 05000456/2023002 and 05000457/2023002 IR 05000454/20230022023-08-0303 August 2023 Integrated Inspection Report 05000454/2023002 and 05000455/2023002 2024-02-02
[Table view] |
Text
UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555*0001 June 6, 2011 Mr. Michael J. Pacilio President and Chief Nuclear Officer Exelon Nuclear 4300 Winfield Road Warrenville, IL 60555
SUBJECT:
BYRON STATION, UNIT NOS. 1 AND 2, AND BRAIDWOOD STATION, UNITS 1 AND 2 - UNACCEPTABLE WITH OPPORTUNITY TO SUPPLEMENT RE: ALTERNATIVES TO THE ASME CODE REQUIREMENTS FOR REPAIRS TO THE REACTOR VESSEL HEAD PENTRATIONS (TAC NOS. ME6071, ME6072, ME6073, AND ME6074)
Dear Mr. Pacilio:
By letter dated April 19, 2011 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML111100620), Exelon Generation Company. LLC (EGC, the licensee). submitted relief requests (RRs) 13R-20 for Byron Station, Unit Nos. 1 and 2, and 13R-09 for Braidwood Station, Units 1 and 2. The RRs proposed an alternative repair technique using weld overlays on the reactor vessel head penetration housing and J-groove welds to assure structural integrity. The purpose of this letter is to provide the results of the NRC staff's acceptance review of RRs 13R-09 and 13R-20. The acceptance review was performed to determine if there is sufficient technical information in scope and depth to allow the NRC staff to complete its detailed technical review. The acceptance review is also intended to identify whether the request has any readily apparent information insufficiencies in its characterization of the regulatory requirements or the licensing basis of the plant.
Pursuant to Sections 50.55a(a)(3)(i) and 50.55a(a)(3)(ii) of Title 10 of the Code of Federal Regulations (10 CFR), the applicant shall demonstrate that the proposed alternatives would provide an acceptable level of quality and safety, or that compliance with the specified requirements of 10 CFR 50.55a would result in hardship or unusual difficulty without a compensating increase in the level of quality or safety.
The NRC staff has reviewed your request and concluded that the information delineated in the enclosure to this letter is necessary to enable the staff to make an independent assessment regarding the acceptability of the proposed RRs in terms of regulatory requirements and the protection of public health, safety, and the environment.
In order to make the request complete, the NRC staff requests that EGC supplement the request to address the information requested in the enclosure by June 14,2011. This will enable the NRC staff to begin its detailed technical review. If the information responsive to the NRC staff request is not received by the above date, the request will not be accepted for review pursuant to 10 CFR 2.101, and the NRC will cease its review activities associated with the RRs.
If the request is subsequently accepted for review, you will be advised of any further information needed to support the NRC staff detailed technical review by separate correspondence.
The information requested and associated timeframe in this letter were discussed with
M. Pacilio - 2 The information requested and associated timeframe in this letter were discussed with Richard Mcintosh of your staff on June 1, 2011.
If you have any questions, please contact the Project Manager, Nicholas DiFrancesco, at (301) 415-1115.
Nicholas DiFrancesco, Project Manager Plant Licensing Branch 111-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket Nos. STN 50-456, STN 50-457, STN 50-454 and STN 50-455
Enclosure:
Supplemental Information Request cc w/encls: Distribution via Listserv
SUPPLEMENTAL INFORMATION REQUEST RELIEF REQUEST 13R-09 BRAIDWOOD STATION, UNITS 1 AND 2 RELIEF REQUEST 13R-20 BYRON STATION, UNIT NOS. 1 AND 2 EXELON GENERATION COMPANY, LLC DOCKET NOS. 50-454, 50-455, 50-456, AND 50-457 By letter dated April 19, 2011, Exelon Generation Company, LLC (EGC, the licensee),
submitted to the U.S. Nuclear Regulatory Commission (NRC) relief requests (RRs) 13R-09 and 13R-20, for the alternative requirements for repair of reactor vessel head penetrations at Braidwood Station, Units 1 and 2, and Byron Stations, Unit Nos. 1 and 2, respectively, for review and approval (Agencywide Documents Access and Management System (ADAMS)
Accession No. ML111100620). The NRC staff finds the RRs 13R-09 and 13R-20 are unacceptable but with an opportunity to supplement additional information supporting the request. The NRC staff requests the following supplemental information to be provided prior to a decision on the acceptability.
(1) Compliance with the ASME Code requires that mechanical defects for the subject seal weld are repaired according to Section III, NB-4450. The requirements of NB-4450 ensure that flaws are completely removed from the weld material. Provide a basis for the definition of a mechanical discontinuity within the subject RR.
(a) Provide a sizing technique for this type of defect and documentation of its demonstrated performance.
(b) Provide a qualified volumetric technique and documentation of its demonstrated performance to accurately depth size and characterize mechanical discontinuities in seal welds for the entire area of coverage of the seal weld over all reactor vessel head penetration nozzle angles.
(c) Provide a qualification plan to demonstrate the performance of equipment, personnel and procedures to implement the techniques of (a) and (b) above.
(2) Provide a basis for assurance that a mechanical discontinuity will be re consumed with additional weld metal as described in Section 5.1.3 of the proposed relief. Demonstration that these mechanical discontinuities are re consumed is to ensure that indications are removed and that latent welding defects do not emerge during future operating cycles.
Enclosure
-2 (a) Demonstrate through mockups the amount of weld material needed to be deposited to re-consume all possible mechanical discontinuities in seal welds for the entire area of coverage of the seal weld over all reactor vessel head penetration nozzle angles. Additionally, please provide a summary table of number of required weld beads and area of coverage requirements to ensure re-consumption.
(b) Provide a qualified volumetric inspection program which will be capable of ensuring the original defect is re-consumed for the entire area of coverage of the seal weld over all reactor vessel head penetration nozzle angles.
(c) Provide a qualification plan to qualify equipment, personnel and procedures to perform (a) and (b) above.
(3) The NRC would review the request to re-consume mechanical discontinuities under the provisions for providing an acceptable level of quality and safety. as opposed to a hardship or unusual difficulty. As such, the NRC will require a basis for equivalent structural integrity of re-consumed mechanical discontinuities to that achieved through compliance with all American Society of Mechanical Engineers,Section III, requirements for application of the weld material.
M. Pacilio -2 The information requested and associated timeframe in this letter were discussed with Richard Mcintosh of your staff on June 1, 2011.
If you have any questions, please contact the Project Manager, Nicholas DiFrancesco, at (301) 415-1115.
Sincerely, IRA by M. Mahoney fori Nicholas DiFrancesco, Project Manager Plant Licensing Branch 111-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket Nos. STN 50-456, STN 50-457, STN 50-454 and STN 50-455
Enclosure:
Supplemental Information Request cc w/encls: Distribution via Listserv DISTRIBUTION:
PUBLIC Branch Reading File RidsAcrsAcnw_MailCTR Resource RidsNrrDorl Resource RidsNrrDorlDpr Resource RidsNrrDorlLpl 3-2 Resource RidsNrrLASRohrer Resource RidsNrrPMBraidwood Resource RidsNrrPMByron Resource RidsOgcRp Resource RidsRgnXMailCenter Resource ADAMS Accession No. ML111330653 NRR-028 OFFICE DORULPL3-2/PM DORULPL3 DCIIBC - via DORULPL3-2/BC I 21 LA electronic memo NAME NDiFrancesco(MMahoney SRohrer TLupold JZimmerman for)
DATE 6/6/11 6/6/11 5/19/11 6/6111 OFFICIAL RECORD COpy